At step 130, a third reflector is configured to direct light from the second subset of LEDs toward α° and at step 132 a fourth reflector is configured to reflect light from this second subset of LEDs towards α°. For example, with reference back to FIG. 6, the reflective surfaces 36, 38, 42 and 44 are each configured to direct light from a respective ring of LEDs generally towards a direction that is 60° offset from vertical.
Illumination is inversely proportional to the square of the distance between the point light source and the surface to be illuminated, i.e. the target area. Because of this law, a light fixture placed x distance (feet or meters) above a planar target area will require four times the light output in a direction that is offset 60° from the vertical axis as compared to the light output in the vertical axis in order to provide the same luminance at each location. Known light sources, incandescent and arc type lamps, account for this by designing a reflector that directs more light toward the periphery of the target area. This design can be accomplished by assuming that the incandescent or arc type light source is a point light source and then appropriately shaping the reflector to accommodate this point light source.
Light emitting diodes (“LEDs”), on the other hand, are typically not powerful enough so that a single LED, which could act as the point light source similar to the incandescent and arc type lamps, provides sufficient illumination of the target area. This is especially the case where the LED is positioned several feet or meters above the target area. Moreover, LEDs typically do not emit light in a spherical pattern, such as incandescent and arc-type lamps, thus making it difficult to design an appropriate reflector.
To provide sufficient illumination for the target area multiple LEDs can be required to provide the sufficient amount of lumens to provide the minimum luminance to meet the project specifications for the target area. LEDs are typically mounted on a printed circuit board (“PCB”) and when a sufficient amount of LEDs are provided on the PCB, however, the size of the PCB required and the number of LEDs required makes it difficult to consider the plurality of LEDs in aggregate as a single point light source. In view of this, it has been known to provide separate optics, either refractive of reflective, for each LED to redirect the light emanating from each LED. Providing a separate optic for each LED can be expensive and also make design of the fixture difficult, especially where it is desirable to provide a light fixture that is easily scalable so that it can be used in a number of different applications.